Inhibition of CBS and the reduction of H2S can increase ROS levels in ovarian cancer cells, inhibit the expression of the ROS-sensitive proteins p53 and p65 and reduce the activity of NF-κB to inhibit the proliferation of cancer cells.19,61 H2S can also affect the activity of NF-κB by affecting the thiolation level of cysteine36 of NF-κB37 or regulating GSH3 and IkB-α levels.19,62 Our results showed that the inhibition of CBS by AOAA or shRNA decreased NF-κB activity, resulting in transcriptional suppression of NF-κB-mediated downstream target gene expression. The gene discussed is TP53; the disease is ovarian cancer.